To push the capability of DH to extremely low photon flux situations, i.e., one photon per pixel or lower, we consider a new hologram formation mechanism with single-photon detection. It opens new possibilities for more advanced holography applications in situations such as probing live cells with minimal light interaction and high-speed volumetric tracking in flow cytometry, where the holograms suffer from poor pattern visibility. This work has been highlighted as a Scilight in the May 2023 issue of APL Photonics.
For the first time, a quanta image sensor (QIS) is integrated into the traditional inline holographic setup as we used in our previous work [1], which is a newly developed image sensor with photon-number-resolving capability. It captures a stack of binary holographic frames created by limited photons with Poisson statistics. Among various photon-counting image sensors reported over the past decade, QIS stands out with its small pixel size (e.g.), high photon detection efficiency, and ultra-low readout noise. For a comprehensive introduction to QIS, please refer to the review paper [2,3].
Integrating QIS in DH is not a trivial task, due to its binary signal detection mechanism and very different noise characteristics, which would require specifically designed reconstruction algorithms. In this work, we designed a physics-informed wavefront reconstruction network called PSHoloNet to reconstruct the object wavefront information from the QIS recordings. It is an unrolled network with task-oriented blocks and loss function. To demonstrate the feasibility through synthetic experiments, we show two DH applications, namely, 3D particle volumetric reconstruction and phase imaging. Please refer to the paper for more details.
@article{zhang2023photon,
title={Photon-starved snapshot holography},
author={Zhang, Yunping and Chan, Stanley H and Lam, Edmund Y},
journal={APL Photonics},
volume={8},
number={5},
pages={056106},
year={2023},
month = {May}
}
You may also be interested in related projects from our group on holographic imaging: